Mr. Reid’s son Rory Reid, a former Clark County commissioner, represented ENN Mojave Energy, a Chinese-backed company seeking to build a $5 billion solar plant near Laughlin, Nev. The company ultimately dropped those plans after failing to secure sufficient financial backing, according to reports.

That project was more than 100 miles from the Bundy Ranch, Ms. Orthman said.

A separate solar project, involving a local Indian tribe, that Mr. Reid has pushed also does not overlap with the Bundy ranch.

“[Harry] Reid’s push for solar energy development in southern Nevada included attendance last month at a groundbreaking ceremony for a solar power facility that involves the Moapa Band of Pauites and First Solar Inc.,” said the KLAS-TV report. “But that 250-megawatt power plant will be roughly 35 miles southwest of the Bundy ranch.”

The BLM cattle roundup began after a 21-year-old court battle between the agency and Mr. Bundy, who has refused to pay federal grazing fees over a dispute about whether the federal government has sovereignty over his land.

Mr. Bundy has said he pays grazing fees to Clark County, Nev., as he has since before the BLM took over management of the lands. The Bundy family has maintained a cattle ranching operation on the southern Nevada property since the 1870s.

“We are so so grateful for the overwhelming show of support. It is clear freedom loving Americans still exist!” said a Monday post on the Bundy Ranch website.

He told Las Vegas radio station KDWN-AM that the demonstrators backing him “have faith in the Constitution.”

“The Founding Fathers didn’t create a government like this,” he said.

The Bundys also have refused to scale back their cattle operation in reaction to the Fish and Wildlife Service’s listing of the desert tortoise as “threatened (similarity of appearance)” in 1990. The Bundy operation is reportedly now the only operating cattle ranch in the area as a result of enforcement efforts aimed at protecting the desert tortoise.

In August, however, the Desert Tortoise Conservation Center in Las Vegas announced that it would begin euthanizing half of the 1,400 tortoises in its 220-acre facility as a result of federal budget cuts, according to The Associated Press.

“The Center is scheduled to close in December 2014 due to funding issues,” said a statement on the BLM’s website. “All healthy tortoises at the Center will be relocated to sites that will support the recovery of the species. Healthy tortoises will not be euthanized.”